The present invention relates to a series of new phenylacetic acid derivatives, which have valuable anti-inflammatory, analgesic and antipyretic activities, to a process for preparing these compounds and to pharmaceutical compositions containing them as the active ingredient.
Mild analgesics and antipyretics are amongst the most commonly used of drugs. Most such drugs in common use have side effects which may be distressing or even dangerous to a small percentage of the population--even though the number of people so afflicted may be statistically insignificant, it is better for such persons to employ a different analgesic, antipyretic or anti-inflammatory drug, whose side effects may not be distressing or dangerous to them, rather than continue with the original drug. There is, therefore, a continuing need for new analgesic, antipyretic and anti-inflammatory drugs, to broaden the choice available to the user.
Amongst the known anti-inflammatory drugs are the (2-oxo-cycloalkylidene)methylphenylacetic acid derivatives disclosed in United Kingdom Patent Specification No. 2,002,762, which were demonstrated to have anti-inflammatory and analgesic activities significantly better than similar commercially available drugs.
We have now discovered a series of phenylacetic acid derivatives which have activities comparable with or better than those of the compounds disclosed in United Kingdom Patent Specification No. 2,002,762 and, in particular, which may have an analgesic activity at least three times better than the prior art compounds.